Ultrasonic gas leak detectors measure the sound pressure waves generated by turbulent flow when gas escapes from higher pressures to the ambient atmosphere. Such gas leak detectors are used as industrial safety devices to monitor the unwanted or unexpected release of combustible or toxic gases into the atmosphere. The leaks need to be identified quickly before they grow further in magnitude, to allow for timely remedial action. Ultrasonic gas leak detectors have the advantage over other gas detector types in that gas does not need to reach the detector; gas leaks can be detected even if the leaking gas is dispersed by wind.
Conventional ultrasonic gas leak detectors are omnidirectional and while providing useful information about the size and duration of a pressurized gas leak do not provide any information to maintenance personnel about the location of the gas leak. Conventional open path detectors, which are line of sight optical detectors, also do not provide leak location information. Conventional point detectors, such as catalytic, infrared or electrochemical, need to be placed in close proximity to each other at added expense to provide for more precise leak location information. Infrared gas cloud imaging cameras are expensive, their sensitivity varies greatly with the gas being monitored, and their performance depends greatly on the differential between the leaking gas cloud and background temperature. For such reasons infrared gas cloud imaging cameras are not being readily adopted in industrial fixed gas detection installations. A need therefore exists to add the benefits of leak location or, at a minimum, leak direction to ultrasonic gas leak detection equipment.